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A293794
Numbers k such that (d(k), d(k+1)) = (1,0) in the base-2 digits d(i) of e.
4
1, 3, 6, 13, 18, 20, 22, 26, 29, 33, 35, 39, 41, 45, 48, 50, 53, 55, 57, 61, 63, 65, 67, 74, 78, 82, 84, 87, 91, 99, 104, 110, 112, 118, 124, 130, 133, 137, 141, 146, 150, 153, 162, 167, 171, 174, 176, 180, 183, 185, 188, 190, 193, 195, 197, 203, 208, 212
OFFSET
1,2
COMMENTS
This sequence, together with A293792, A293793 and A293795, partitions the positive integers.
LINKS
EXAMPLE
(d(i)) = (1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,...) = A004593, in which (1,0) first occurs as (a(1),a(2)).
MATHEMATICA
z = 100; s = StringJoin[Map[ToString, First[RealDigits[N[E], 10000], 2]]]];
Take[Map[#[[1]]&, StringPosition[s, "00"]], z] (*A293792*)
Take[Map[#[[1]]&, StringPosition[s, "01"]], z] (*A293793*)
Take[Map[#[[1]]&, StringPosition[s, "10"]], z] (*A293794*)
Take[Map[#[[1]]&, StringPosition[s, "11"]], z] (*A293795*)
(* Peter J. C. Moses, Oct 15 2017 *)
SequencePosition[RealDigits[E, 2, 250][[1]], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 29 2019 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Oct 20 2017
STATUS
approved